Lavochkin La-7

1944

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Lavochkin La-7

The ultimate refinement of the basic La-5 rather than a new design, the La-7 was developed from the autumn of 1943 under the bureau designation of La-120. This embodied the results of a TsAGI wind tunnel programme aimed at defining areas in which the basic La-5FN could be aerodynamically improved. Incorporating the modified wing structure (metal spars replacing the wooden box spars) intended for application to the definitive La-5FN (but not to be introduced on that fighter until the late spring of 1944), a revised inboard wing leading edge and an entirely new cowling for the Shvetsov M-82FN engine, the La-120 was first flown in November 1943. In the following spring it entered production as the La-7. The intended armament comprised three 20mm Berezina B-20 cannon, but while this armament was installed in aircraft built at Yaroslavl, those built at Moscow reverted to the twin ShVAK cannon of the La-5FN. Variants included the tandem two-seat La-7UTI trainer, the La-7TK with a pair of TK-3 turbo-superchargers, and the rocket-boosted La-7R. The La-7TK was test flown in July- August 1944, but was destroyed when a turbo-supercharger exploded. Another example was fitted with the 2000hp ASh-71TK, trials soon being discontinued owing to the erratic behaviour of this engine's turbosuperchargers.

The La-7R, of which two prototypes were tested, was fitted in the rear fuselage with an RD-lKhZ liquid rocket motor of 300kg thrust, the first prototype being destroyed during the initial take-off run in October 1944. Flight testing of the second prototype continued until February 1945, and a further example - a conversion of one of the original prototype airframes and therefore referred to as the La-120R - entered test in January 1945, this having an improved rocket motor and local airframe structural changes. Testing of the La-120R continued until late 1946.

A total of 5,753 La-7s had been manufactured when production ended in 1946.

Lavochkin La-7

Specification 
 CREW1
 WEIGHTS
  Take-off weight3400 kg7496 lb
  Empty weight2620 kg5776 lb
 DIMENSIONS
  Wingspan9.8 m32 ft 2 in
  Length8.6 m28 ft 3 in
  Height2.60 m9 ft 6 in
  Wing area17.59 m2189.34 sq ft
 PERFORMANCE
  Max. speed680 km/h423 mph
  Cruise speed450 km/h280 mph
  Ceiling11800 m38700 ft
  Range990 km615 miles

3-View 
Lavochkin La-7A three-view drawing (1653 x 1193)

Comments1-20 21-40
Zhengyang Wang, e-mail, 26.08.2022 23:12

Some evidence seen that there were few La 7 fighters equipped the NS23-S 23mm synchonized cannon.As far as I know,the caliber of propeller fighter's synchonized gun up to 20-23mm. Each aircrafts guns behind propeller up to 4.Which restrict single-engine aircraft's firepower.Few of cannons can be synchonized cannon:20mm Japanese Ho-5,German 20mm MG151-20,Soviet 20mm Shvak and Berlizen B20S,23mm NS23S.
It is true that only La-9 and La-11 equipped with NS-23S cannons.Which have ability to fire 23mm shells through the propeller. I am interested about the La-7 with NS-23S cannon.

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lxbfYeaa, e-mail, 14.03.2024 Zhengyang Wang

20

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npqlnuupfs, e-mail, 30.07.2020 00:31

Muchas gracias. ?Como puedo iniciar sesion?

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Ron, e-mail, 02.01.2015 09:07

If the 3xB-20 put out 3.4 kg per sec, that's 11.8 shells each (sync)! 708 rpm.

The ShVAK 20 is 610-615 rpm for 10.25-10.5 rps. A twin cannon salvo would be about 21 rps or 2.016 kg /sec.

Elsewhere I've seen .95 kg per sec. In that case it would be 9.9 rps or 594 rpm for a 1.9 kg /sec twin salvo.

I don't have expertease on this, just numbers I find for what it's worth.

True, it's light for a 20 like the IJAAF Ho-5, but these both are tops for RoF needed in dogfights and they beat HMGs with at least double firepower not counting HE blast.

The VYa-23 sync RoF is 370-500 rpm. Some La-5s had them installed whenever the factory ran short on ShVAKs.

I wouldn't lean too far toward the 500 rate because the faster cowl-mounted NS-23 did 500 rpm on the post-war La-9.
It sported 4xNS-23 cannons but a less powerful 23mm cartridge.
A few hundred Yak-9UT fighters had these hub-mounted in time for the battle of Berlin.
The mid-point would be 435 rpm which would be more reliable but still just an average in the absence of more detail.

This one beats the Hispano 20 in power. Of course it can't be synchronized, but otherwise the RoF and M /V are close.

Of course the 200 g shell of the 23mm VYa handily beats the Hispano 130 g 20mm shell!

Some Yaks had the VYa-23 hub gun with a RoF up to 600 rpm like the Hispano 20. A salvo was 2 kg /sec vs 1.3 kg /sec.

With HE, No contest!

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Ron, e-mail, 20.12.2014 00:34

The synchronized B-20 weight of fire contradicts a published RoF of 600 rpm for it. That could be a better rate for reliability vs a maximum rate.

For example, the unsynchronized VYa-23 cannon had a RoF up to 650 rpm but a more reliable range was 540-570 (some Yaks hub-mounted...etc).
The ammo was 210 g API @ 885 mps M /V;
196 g HET @ 900 mps and 12 g RDX;
and 198 g HEI @ 905 mps and 15 g filler!

Awsome for 2 guns against bombers etc... Even though too low a synchronized RoF for dogfights.

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Ron, e-mail, 08.07.2014 08:51

Some Russians felt the shells weren't heavy enough. But then they also had the Vya-23! Some Lavochkins got them when the 20mm was unavailable. It was a little slower but twice as powerful. Great for tackling bombers. The Il-2 Shturmovik made this cannon famous.

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Ron, e-mail, 08.07.2014 08:23

ROF per B-20 is about 710 rpm per synchronized cannon thus the average shell is 95.77g for 3.4 Kg per second weight of fire.
If the normal cyclic rate is 800 rpm it is an 88.8% rate to synchronize for the La-7 or in other words, a penalty of 11.2%. That's not bad. 35.5 shells per second from 3 B-20s!
The steller performance is likely due to its light weight round compared to 130g per shell for the Hispano for example. Or the Type 99 with a 128g shell. Both of which were far slower, nevermind a synchronized rate. No can do.
The Ho-5 is similarly on the light side like the B-20 and faster until synchronized. Then it slows from 850 rpm to 400! The MG151 /20 is somewhere in the middle.

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Ron, e-mail, 22.02.2014 00:15

Tails,
Could you elaborate?

When Germans looked down there noses at captured Soviet planes for their lack of western style sophistication, they had contempt like you and most all the rest of us in the West. But this faded after a Russian winter or 2. The crude Russian planes were in the air when the luftwaffe was frozen
in place.

Fact is Soviet fighters were tailored to their own theater of combat like no others. Low to medium altitude, short range tactical air superiority in spite of the canopy glass not being the clearest or the gunsight behind the times.
They would not stack up as well in the wide ranging Pacific theater where the USA and Japan ruled.

Their pilots too were mostly not as well trained perhaps.
Still, the top scoring Allied aces were Soviet!

While I'm not communist or anything, if I were Russian maybe I would like this site also, to Wills point.

If we get past our own propaganda, we have to recognize the efficiency of Soviet weapons and what they managed with the limited power their designers had to work with. Even their Lavochkin and Yakovlev wartime production is on par with Bf 109 and Fw 190 numbers, never mind that of other fighters (only the Spitfire numbers approach such volume). Those 5 are on top with 20 to 35 thousand during WW2
(the Sturmovik is up there too but it's not a single seat fighter so I won't mention it).

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Ron, e-mail, 07.01.2014 00:32

Who could help me translate from russian to englsh?

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tails, 07.12.2012 17:50

no just no

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Klaatu83, e-mail, 19.08.2012 03:26

Although the LaGG-3 was a disappointment, Lavochkin went back to the drawing board and got it right with the LA-5FN. The LA-7 was even better. Both are considered to be among the best fighters of World War II. And yes, a LA-7 DID shoot down a Me-262!

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anti-redneck, e-mail, 26.04.2012 18:36

Just wanted to say - laughing out loud at that Will Gant guy. Go get you' gun redneck and teach these POS's how to make a site. Oh these people...
P.S. Real communism is dead for 25 years already.

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anti-redneck, e-mail, 26.04.2012 18:36

Just wanted to say - laughing out loud at that Will Gant guy. Go get you' gun redneck and teach these POS's how to make a site. Oh these people...
P.S. Real communism is dead for 25 years already.

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Sven, 21.01.2012 21:14

Hey Will.
Spelling. 2 /10
Grammar. 1 /10
Knowledge. 1 /10
W think that's 4 out of a possible 30. Some research into Barbarosa would serve you well.

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Will Gant, e-mail, 21.01.2012 18:37

The La7 is most games is optomized per the propoganda here. Russian fuel quality alone insured that their cruddy air force would only start 70% of the time. The Russian's had interesting armor, but nothing for an air force that ever worried a German pilot. They simply had so many bad planes, the Messershmidt's were outnumbered everytime. Owen can't even get the model type right when quoting his joy of flying this commie POS online.

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Aaron, e-mail, 26.06.2011 18:48

In November 1944 all production irregularities had been worked out and production resumed of the La-7. This later production models performance was: Same Engine. 382mph /SL.
421-423mph /20,200ft. Climb: 4,300fpm /SL. 16,400ft /4.2min. Ceiling: 34,450ft. Test weight 7,105 lbs. 2xShVAK (20mm).
The last war time production model was unchanged except the armament. In February 1945 3xB-20s became the standard armament. Weight was increased to 7,325 but performance was unchanged. 115 La-7 were lost to all military causes (less than half of these to aerial combat) at the same time unquestionably accounting for more than 3,100 aerial victories. That's about 27:1 win /loss ratio for all military losses. Handling and control harmony were superlative. Roll rate was considered equal to any Fw-190A.
Entire formations of German aircraft were routinely decimated by flights of La7s. 10,009 La-5 and 5,753 La-7 had been produced by the end of the Great Patriotic War.

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Aaron, e-mail, 26.06.2011 18:25

The first series production La-7 were produced in March-April of 1944. That Summer they were handed over to the pilots of 63 GIAP for operational trials. Though they had inferior performance to what was expected the pilots were thrilled to receive the La-7 and enjoyed great success with this aircraft until engine problems and wing spar failures forced Marshal Novikov to step in an ground all La-7s until the problems could be rectified. The causes were dirt getting into the supercharger air intake at the wingroots and improper execution of lightening holes in the structure. Typical performance: Engine: ASh-82FN /1,850hp.
362mph /SL. 413mph /20,200ft. Climb: 4,000fpm /SL. 16,400ft /4.6min. Ceiling: 31,000ft. Armament: 2xShVAK. Test weight: 7,179 lbs.

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Peredtz, e-mail, 23.03.2010 13:19

Ron, the source page for the shot Mustang photos describers the incident in Russian as having happened on April 17, 1945 over Berlin. It is also mentioned that it was one of the two Mustangs shot by Kozhedub that day. This really was friendly fire since American mistakingly fighters attacked Kozhedub after he had tried to cover B-17s by engaging German Messerschmitts. The Americans misinterpreted his intentions and tried to shoot him down. He says he realised these were allies only after one of them had gone down for an emergency landing and another one had exploded midair. The fact was later on proven by the processed guncam film. The incident was not widely covered at the time, cause the survivor Mustang pilot believed he was downed by a red-nosed FW. The info here is coming from the preface to the book of memoirs by Kozhedub. Quoted from there at www.airpages.ru /ru /la7_2.shtml, at least.

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Ron, e-mail, 12.02.2010 07:21

Eliko,
When and where was that shot? Europe or Korea?
Probably Europe if the camera is on an La-7, but exactly where? Interesting photo!
Is there anything about the circumstances of this 'friendly fire' combat?
I've read in the past about such a clash with Yaks and Mustangs. Please tell me more about this La-7 vs P-51 incident.

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eliko, e-mail, 08.10.2009 21:48

guncam Kozhedub shut down Mustang ...
www.airpages.ru /img /ru /la7-must.jpg

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Ronald, e-mail, 18.06.2009 04:21

Ivan Kozhedub was the top scoring Allied ace in history and he flew Lavochkin fighters. He even shot down a German Me 262 jet with the stock La-7 (not the one with rocket assist). The Spitfire XIV was first to do so in the West. The La-7 units would get the call when low flying bandits were too fast for the Yak-9U to catch. The version with 3 light-weight B-20 nose-cannon was particularly effective. It was a beautiful aerobatic dogfighter. So was it's rival, the Yak, but the Lavochkin could take more punishment. It was right at home in a rugged ground war since it excelled at low to medium altitudes.

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1-20 21-40

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